Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Portland State University

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 1981 - 2010 of 3798

Full-Text Articles in Physical Sciences and Mathematics

The Effects Of Large Wildfires On Employment And Wage Growth And Volatility In The Western United States, Max Nielsen-Pincus, Cassandra Moseley, Krista Gebert Nov 2013

The Effects Of Large Wildfires On Employment And Wage Growth And Volatility In The Western United States, Max Nielsen-Pincus, Cassandra Moseley, Krista Gebert

Environmental Science and Management Faculty Publications and Presentations

We examined the effect of large wildfires on economic growth and volatility in the western United States. We matched wildfire data with quarterly employment and earnings growth data to assess the specific effect of wildfire on employment and wage growth in western US counties. Wildfires generally tended to exhibit positive effects on employment and wage growth in the quarter(s) during which suppression efforts were active. However, this effect transitioned to increased economic volatility following a wildfire. The effect of wildfire also varied by the type of county in which wildfire occurred. The amount of suppression costs invested locally had the …


Methyl Halide Production By Calcareous Periphyton Mats From The Florida Everglades, Ann Eileen Raffel Oct 2013

Methyl Halide Production By Calcareous Periphyton Mats From The Florida Everglades, Ann Eileen Raffel

Dissertations and Theses

Methyl halides are trace gases with both natural and anthropogenic origins. Once generated, these gases transport chlorine and bromine into the stratosphere, where they play an important role in ozone depleting catalytic cycles. The Florida Everglades is one location where methyl halide emissions have been proposed to be elevated due to high primary production and ionic halogens. This region also provides a unique study environment due to salt water intrusions, which occur during storm or low marsh water level-high tide events. The purpose of this research was twofold. First, quantification of methyl chloride (CH3Cl) and methyl bromide (CH …


Effects Of Water Development On Arid Land Freshwater Ecosystems, Angela L. Strecker Oct 2013

Effects Of Water Development On Arid Land Freshwater Ecosystems, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

This presentation focuses on the Columbia Basin Project


Emerging Contaminants In Oregon Coastal Waters: Hotspots, Landscape Drivers And Synergistic Effects On Bivalves, Elise F. Granek, William Fish, Angela L. Strecker Oct 2013

Emerging Contaminants In Oregon Coastal Waters: Hotspots, Landscape Drivers And Synergistic Effects On Bivalves, Elise F. Granek, William Fish, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

This presentation focuses on the following research questions:

  • Types and levels of contaminants of emerging concern (CECs) in Oregon’s coastal ocean?
  • Levels of CECs in native and commercial oysters?
  • Ecological effects (growth, reproductive output, etc.) of these contaminants in marine bivalves?


The Eugene Water And Electric Board’S Mckenzie River Payment For Watershed Services Program: Research Findings On Ratepayers, Landowners, And Local Stakeholders, Max Nielsen-Pincus Oct 2013

The Eugene Water And Electric Board’S Mckenzie River Payment For Watershed Services Program: Research Findings On Ratepayers, Landowners, And Local Stakeholders, Max Nielsen-Pincus

Environmental Science and Management Faculty Publications and Presentations

This presentation focuses on the following research objectives:

  • How much are ratepayers willing to pay and what effects that willingness?
  • How much do landowners need to receive and what affects their interest?


Getting Salmon Back In Salmon Creek: Systematizing Comparative Water Quality Analysis For Targeted Restoration, Zbigniew J. Grabowski, Sarah Janjua, Michael Swamer, Heejun Chang, Eric Watson Oct 2013

Getting Salmon Back In Salmon Creek: Systematizing Comparative Water Quality Analysis For Targeted Restoration, Zbigniew J. Grabowski, Sarah Janjua, Michael Swamer, Heejun Chang, Eric Watson

Geography Faculty Publications and Presentations

This presentation focuses on water quality restoration efforts in Salmon Creek


Engaging Stakeholders In Ecosystem Service Assessment Under Climate Change And Urban Development Scenarios, Heejun Chang, David E. Ervin, Wes Hoyer, Mike Psaris, Ken Lyons, Emily D. Dietrich, Samantha Hamlin, John Lambrinos, Tammy Winfield, Bobby Cochran Oct 2013

Engaging Stakeholders In Ecosystem Service Assessment Under Climate Change And Urban Development Scenarios, Heejun Chang, David E. Ervin, Wes Hoyer, Mike Psaris, Ken Lyons, Emily D. Dietrich, Samantha Hamlin, John Lambrinos, Tammy Winfield, Bobby Cochran

Geography Faculty Publications and Presentations

This presentation focuses on how scientists can engage stakeholders in ecosystem service assessment.


Multi-Level Surface Enhanced Raman Scattering Using AgoX Thin Film, Ming Lun Tseng, Chia Min Chang, Bo Han Cheng, Pin Chieh Wu, K. S. Chung, M. K. Hsiao, H. W. Huang, D. W. Huang, Hai-Pang Chiang, P.T. Leung, D. P. Tsai Oct 2013

Multi-Level Surface Enhanced Raman Scattering Using AgoX Thin Film, Ming Lun Tseng, Chia Min Chang, Bo Han Cheng, Pin Chieh Wu, K. S. Chung, M. K. Hsiao, H. W. Huang, D. W. Huang, Hai-Pang Chiang, P.T. Leung, D. P. Tsai

Physics Faculty Publications and Presentations

Ag nanostructures with surface-enhanced Raman scattering (SERS) activities have been fabricated by applying laser-direct writing (LDW) technique on silver oxide (AgOx) thin films. By controlling the laser powers, multi-level Raman imaging of organic molecules adsorbed on the nanostructures has been observed. This phenomenon is further investigated by atomic-force microscopy and electromagnetic calculation. The SERS-active nanostructure is also fabricated on transparent and flexible substrate to demonstrate our promising strategy for the development of novel and low-cost sensing chip.


Carbon Dynamics In The Future Forest: The Importance Of Long-Term Successional Legacy And Climate–Fire Interactions, E. Louise Loudermilk, Robert M. Scheller, Peter J. Weisberg, Jian Yang, Thomas E. Dilts, Sarah L. Karam, Carl Skinner Oct 2013

Carbon Dynamics In The Future Forest: The Importance Of Long-Term Successional Legacy And Climate–Fire Interactions, E. Louise Loudermilk, Robert M. Scheller, Peter J. Weisberg, Jian Yang, Thomas E. Dilts, Sarah L. Karam, Carl Skinner

Environmental Science and Management Faculty Publications and Presentations

Understanding how climate change may influence forest carbon (C) budgets requires knowledge of forest growth relationships with regional climate, long-term forest succession, and past and future disturbances, such as wildfires and timber harvesting events. We used a landscape-scale model of forest succession, wildfire, and C dynamics (LANDIS-II) to evaluate the effects of a changing climate (A2 and B1 IPCC emissions; Geophysical Fluid Dynamics Laboratory General Circulation Models) on total forest C, tree species composition, and wildfire dynamics in the Lake Tahoe Basin, California, and Nevada. The independent effects of temperature and precipitation were assessed within and among climate models. Results …


Visualization Of Optical Wave Propagation In Femtosecond Photoemission Electron Microscopy, Rolf Kӧnenkamp, Robert Campbell Word, Joseph Fitzgerald Oct 2013

Visualization Of Optical Wave Propagation In Femtosecond Photoemission Electron Microscopy, Rolf Kӧnenkamp, Robert Campbell Word, Joseph Fitzgerald

Physics Faculty Publications and Presentations

Photoemission electron microscopy (PEEM) combines in a unique way photon probing and electron imaging. The imaging electrons are generated in a photoelectric process by illuminating the sample with ultra-violet or x-ray light. After generation these electrons are accelerated and introduced into an electron-optical system to produce a microscopic image of the specimen surface. The advantages of PEEM are manifold:

The avoidance of electron beam exposure makes PEEM a much gentler method than standard electron microscopy. This advantage is important when fragile organic or biological structures are studied. PEEM is also highly surface sensitive, since the photoelectrons typically escape the sample …


Zno Nanoneedle/H2o Solid-Liquid Heterojunction-Based Self-Powered Ultraviolet Detector, Qinghao Li, Lin Wei, Yanru Xie, Kai Zhang, Lei Liu, Dapeng Zhu, Jun Jiao, Yanxue Chen, Shishen Yan, Guolei Liu, Liangmo Mei Oct 2013

Zno Nanoneedle/H2o Solid-Liquid Heterojunction-Based Self-Powered Ultraviolet Detector, Qinghao Li, Lin Wei, Yanru Xie, Kai Zhang, Lei Liu, Dapeng Zhu, Jun Jiao, Yanxue Chen, Shishen Yan, Guolei Liu, Liangmo Mei

Physics Faculty Publications and Presentations

ZnO nanoneedle arrays were grown vertically on a fluorine-doped tin oxide-coated glass by hydrothermal method at a relatively low temperature. A self-powered photoelectrochemical cell-type UV detector was fabricated using the ZnO nanoneedles as the active photoanode and H2O as the electrolyte. This solid-liquid heterojunction offers an enlarged ZnO/water contact area and a direct pathway for electron transport simultaneously. By connecting this UV photodetector to an ammeter, the intensity of UV light can be quantified using the output short-circuit photocurrent without a power source. High photosensitivity, excellent spectral selectivity, and fast photoresponse at zero bias are observed in this UV detector. …


Environmental Factors Influencing Diatom Communities In Antarctic Cryoconite Holes, Lee F. Stanish, Elizabeth A. Bagshaw, Diane M. Mcknight, Andrew G. Fountain, Martyn Tranter Oct 2013

Environmental Factors Influencing Diatom Communities In Antarctic Cryoconite Holes, Lee F. Stanish, Elizabeth A. Bagshaw, Diane M. Mcknight, Andrew G. Fountain, Martyn Tranter

Geology Faculty Publications and Presentations

Cryoconite holes are ice-bound habitats that can act as refuges for aquatic and terrestrial microorganisms on glacier surfaces. In the McMurdo Dry Valleys of Antarctica, these holes are often capped by an ice lid that prevents the exchange of material and gases with the surrounding atmosphere and aquatic environment. Diatoms have been documented in cryoconite holes, and recent findings suggest that these habitats may harbour a distinctive diatom flora compared to the surrounding aquatic environments. In this study, we examined diatom community composition in cryoconite holes and environmental correlates across three glaciers in Taylor Valley, Antarctica. The diatom communities were …


Effects Of Runoff Sensitivity And Catchment Characteristics On Regional Actual Evapotranspiration Trends In The Conterminous Us, Il-Won Jung, Heejun Chang, John Risley Oct 2013

Effects Of Runoff Sensitivity And Catchment Characteristics On Regional Actual Evapotranspiration Trends In The Conterminous Us, Il-Won Jung, Heejun Chang, John Risley

Geography Faculty Publications and Presentations

An understanding of the role of hydro-climatic and geographic regimes on regional actual evapotranspiration (AET) change is essential to improving our knowledge on predicting water availability in a changing climate. This study investigates the relationship between AET change for a 60 year period (1951–2010) and the runoff sensitivity in 255 undisturbed catchments over the US. The runoff sensitivity to climate change is simply defined as the relative magnitude between runoff and precipitation changes with time. Runoff sensitivity can readily explain the conflicting directions of AET changes under similar precipitation change. Under increasing precipitation, AET decreases when runoff is increasing more …


Optics And Spectroscopy In Massive Electrodynamic Theory, Adam Caccavano Oct 2013

Optics And Spectroscopy In Massive Electrodynamic Theory, Adam Caccavano

Dissertations and Theses

The kinematics and dynamics for plane wave optics are derived for a massive electrodynamic field by utilizing Proca's theory. Atomic spectroscopy is also examined, with the focus on the 21 cm radiation due to the hyperfine structure of hydrogen. The modifications to Snell's Law, the Fresnel formulas, and the 21 cm radiation are shown to reduce to the familiar expressions in the limit of zero photon mass.


Evaluation Of Phase Change Materials For Cooling In A Super-Insulated Passive House, Jeffrey Stephen Lauck Oct 2013

Evaluation Of Phase Change Materials For Cooling In A Super-Insulated Passive House, Jeffrey Stephen Lauck

Dissertations and Theses

Due to factors such as rising energy costs, diminishing resources, and climate change, the demand for high performance buildings is on the rise. As a result, several new building standards have emerged including the Passive House Standard, a rigorous energy-use standard based on a super-insulated and very tightly sealed building envelope. The standard requires that that air infiltration is less than or equal to 0.6 air changes per hour at a 50 Pascal pressure difference, annual heating energy is less than or equal to 15kWh/m2, and total annual source energy is less than or equal to 120 kWh/m2. A common …


Oregon Dreissenid Mussel: Rapid Response Plan, Robyn Draheim, Rick Boatner, Glenn Dolphin, Lisa Debruyckere Oct 2013

Oregon Dreissenid Mussel: Rapid Response Plan, Robyn Draheim, Rick Boatner, Glenn Dolphin, Lisa Debruyckere

Center for Lakes and Reservoirs Publications and Presentations

In 2007, both zebra mussels (Dreissena polymorpha) and quagga mussels (Dreissena rostriformis bugensis) were found to have established populations west of the Rocky Mountains. The risk posed to the Pacific Northwest by the proximity of these new infestations is significant. This plan was developed in response to the increasing likelihood of the successful transport and introduction of these species into the State of Oregon and Pacific Northwest. Although prevention remains the most cost-effective means of addressing potential infestations of aquatic invasive species, if prevention efforts fail, the State of Oregon must be prepared to respond rapidly …


Commute-Friendly, Gas-Electric Hybrid Vehicle Testing, James Long, Hugh Currin, Xin Wang Oct 2013

Commute-Friendly, Gas-Electric Hybrid Vehicle Testing, James Long, Hugh Currin, Xin Wang

TREC Final Reports

Overview: Green Lite Motors is a Portland-based company building a hybrid commuter vehicle targeted for urban and suburban areas. The vehicle is a front/back, two-seat configuration with three wheels (two front and one rear-drive wheel). The vehicle is classed as a motorcycle, giving it all the advantages of a smaller footprint in parking and highway travel; however, the advanced roll-cage design and fairing give the vehicle safety and comfort advantages of a standard passenger car. The unique combination of internal combustion engine and electric motor give the vehicle mileage possibilities greater than 100 mpg as well as the convenience and …


Multigrid For An Hdg Method, Bernardo Cockburn, O. Bubois, Jay Gopalakrishnan Oct 2013

Multigrid For An Hdg Method, Bernardo Cockburn, O. Bubois, Jay Gopalakrishnan

Mathematics and Statistics Faculty Publications and Presentations

We analyze the convergence of a multigrid algorithm for the Hybridizable Discontinuous Galerkin (HDG) method for diffusion problems. We prove that a non-nested multigrid V-cycle, with a single smoothing step per level, converges at a mesh independent rate. Along the way, we study conditioning of the HDG method, prove new error estimates for it, and identify an abstract class of problems for which a nonnested two-level multigrid cycle with one smoothing step converges even when the prolongation norm is greater than one. Numerical experiments verifying our theoretical results are presented.


Late Holocene Tsunami Deposits At Salt Creek, Washington, Usa, Ian Hutchinson, Curt D. Peterson, Sarah L. Sterling Oct 2013

Late Holocene Tsunami Deposits At Salt Creek, Washington, Usa, Ian Hutchinson, Curt D. Peterson, Sarah L. Sterling

Anthropology Faculty Publications and Presentations

We interpret two thin sand layers in the estuarine marsh at Salt Creek, on the southern shore of the Strait of Juan de Fuca, as the products of tsunamis propagated by earthquakes at the Cascadia subduction zone. The sand layers extend for about 60 m along the left bank of the creek about 800 m from the mouth, and can be traced to the base of a nearby upland area. One layer is exposed in the creek bank about 400 m further upstream, but they are only patchily distributed in the rest of the central area of the marsh. Both …


A Primal Dpg Method Without A First-Order Reformulation, L. Demkowicz, Jay Gopalakrishnan Oct 2013

A Primal Dpg Method Without A First-Order Reformulation, L. Demkowicz, Jay Gopalakrishnan

Mathematics and Statistics Faculty Publications and Presentations

We show that it is possible to apply the DPG methodology without reformulating a second-order boundary value problem into a first-order system, by considering the simple example of the Poisson equation. The result is a new weak formulation and a new DPG method for the Poisson equation, which has no numerical trace variable, but has a numerical flux approximation on the element interfaces, in addition to the primal interior variable.


Climate Change And Fire Management In The Mid-Atlantic Region, Kenneth L. Clark, Nicholas Skowronski, Heidi Renninger, Robert M. Scheller Oct 2013

Climate Change And Fire Management In The Mid-Atlantic Region, Kenneth L. Clark, Nicholas Skowronski, Heidi Renninger, Robert M. Scheller

Environmental Science and Management Faculty Publications and Presentations

In this review, we summarize the potential impacts of climate change on wildfire activity in the mid­-Atlantic region, and then consider how the beneficial uses of prescribed fire could conflict with mitigation needs for climate change, focusing on patters of carbon (C) sequestration by forests in the region. We use a synthesis of field studies, eddy flux tower measurements, and simulation studies to evaluate how the use of prescibed fire affects short-and long-term forest C dynamics. Climate change may create weather conditions more conducive to wildfire activity, but successional changes in forest composition, altered gap dynamics, reduced understory and forest …


Search Tool That Utilizes Scientific Metadata Matched Against User-Entered Parameters, Veronika Margaret Megler, David Maier Oct 2013

Search Tool That Utilizes Scientific Metadata Matched Against User-Entered Parameters, Veronika Margaret Megler, David Maier

Computer Science Faculty Publications and Presentations

A method for providing proximate dataset recommendations can begin with the creation of metadata records corresponding to datasets that represent scientific data by a scientific dataset search tool. The metadata records can conform to a standardized structural definition, and may be hierarchical. Values for the data elements of the metadata records can be contained within the datasets. Metadata records with a value that is proximate to a user-entered search parameter can be identified. A proximity score can be calculated for each identified metadata record. The proximity score can express a relevance of the corresponding dataset to the user-entered search parameters. …


Trust-But-Verify: Guaranteeing The Integrity Of User-Generated Content In Online Applications, Akshay Dua Sep 2013

Trust-But-Verify: Guaranteeing The Integrity Of User-Generated Content In Online Applications, Akshay Dua

Dissertations and Theses

Online applications that are open to participation lack reliable methods to establish the integrity of user-generated information. Users may unknowingly own compromised devices, or intentionally publish forged information. In these scenarios, applications need some way to determine the "correctness" of autonomously generated information. Towards that end, this thesis presents a "trust-but-verify" approach that enables open online applications to independently verify the information generated by each participant. In addition to enabling independent verification, our framework allows an application to verify less information from more trustworthy users and verify more information from less trustworthy ones. Thus, an application can trade-off performance for …


Characterization Of Secondary Organic Aerosol Precursors Using Two-Dimensional Gas Chromatography With Time Of Flight Mass Spectrometry (Gc×Gc/Tofms), Melissa Jordan Roskamp Sep 2013

Characterization Of Secondary Organic Aerosol Precursors Using Two-Dimensional Gas Chromatography With Time Of Flight Mass Spectrometry (Gc×Gc/Tofms), Melissa Jordan Roskamp

Dissertations and Theses

The oxidation of volatile organic compounds (VOCs) plays a role in both regional and global air quality through the formation of secondary organic aerosols (SOA). More than 1000TgC/yr of non-methane VOCs are emitted from biogenic sources (significantly greater than from anthropogenic sources). Despite this magnitude and potential importance for air quality, the body of knowledge around the identities, quantities and oxidation processes of these compounds is still incomplete (e.g., Goldstein & Galbally, 2007; Robinson et al., 2009). Two-dimensional gas chromatography paired with time-of-flight mass spectrometry (GC×GC/TOFMS) is a powerful analytical technique which is explored here for its role in better …


Building A Knowledge Base: Understanding Prospective Elementary Teachers’ Mathematical Content Knowledge, Eva Thanheiser, Christine Browning, Alden Edson, Signe Kastberg, Jane-Jane Lo Sep 2013

Building A Knowledge Base: Understanding Prospective Elementary Teachers’ Mathematical Content Knowledge, Eva Thanheiser, Christine Browning, Alden Edson, Signe Kastberg, Jane-Jane Lo

Mathematics and Statistics Faculty Publications and Presentations

This survey of the literature summarizes and reflects on research findings regarding elementary preservice teachers’ (PSTs’) mathematics conceptions and the development thereof. Despite the current focus on teacher education, peer-reviewed journals offer a surprisingly sparse insight in these areas. The limited research that exists chiefly presents views of PSTs’ reasoning at singular points during a term, thus focusing on conceptions almost to the exclusion of the their development. We summarize the current findings, which are a beginning of a collective understanding of PSTs’ mathematical content knowledge. We believe much more work is needed to understand how PSTs can best develop …


Job Growth And Loss Across Sectors And Time In The Western Us: The Impact Of Large Wildfires, Max Nielsen-Pincus, Cassandra Moseley, Krista Gebert Sep 2013

Job Growth And Loss Across Sectors And Time In The Western Us: The Impact Of Large Wildfires, Max Nielsen-Pincus, Cassandra Moseley, Krista Gebert

Environmental Science and Management Faculty Publications and Presentations

The link between economic growth and natural hazards has long been studied to better understand the effects of natural hazards on local, regional, and country level growth patterns. However, relatively little generalizable research has focused on wildfires, one of the most common forest disturbances in the western United States (US). We examined the effect of large wildfires on employment growth across sectors and time in the western US.We matched wildfire occurrences from 2004 to 2008 and their duration with monthly employment data to identify the effect of wildfire on employment growth. Wildfires generally tended to exhibit positive effects on employment …


Accommodation Space Controls On The Latest Pleistocene And Holocene (16–0 Ka) Sediment Size And Bypassing In The Lower Columbia River Valley: A Large Fluvial–Tidal System In Oregon And Washington, Usa, Curt D. Peterson Sep 2013

Accommodation Space Controls On The Latest Pleistocene And Holocene (16–0 Ka) Sediment Size And Bypassing In The Lower Columbia River Valley: A Large Fluvial–Tidal System In Oregon And Washington, Usa, Curt D. Peterson

Geology Faculty Publications and Presentations

In this study, we establish the roles that increasing basin accommodation space have on sediment size and bypassing in the transgressive fill (16–0 ka) in the submerged Lower Columbia River Valley (LCRV). The antecedent forearc valley (225 km in length, 4–8 km in width, and 60–115 m in axial valley depth) is characterized by high sediment supply rates (10–15 million t y-1) but no delta at its mouth to the Pacific Ocean. Core sample sediment textures (N ¼ 1600) are analyzed from 3000 m of borehole sections in 58 representative boreholes to characterize the ancestral valley fill: 57% sand, 17% …


Faulty Measurements And Shaky Tools: An Exploration Into Hazus And The Seismic Vulnerabilities Of Portland, Or, Brittany Ann Brannon Aug 2013

Faulty Measurements And Shaky Tools: An Exploration Into Hazus And The Seismic Vulnerabilities Of Portland, Or, Brittany Ann Brannon

Dissertations and Theses

Events or forces of nature with catastrophic consequences, or "natural disasters," have increased in both frequency and force due to climate change and increased urbanization in climate-sensitive areas. To create capacity to face these dangers, an entity must first quantify the threat and translate scientific knowledge on nature into comprehensible estimates of cost and loss. These estimates equip those at risk with knowledge to enact policy, formulate mitigation plans, raise awareness, and promote preparedness in light of potential destruction. Hazards-United States, or Hazus, is one such tool created by the federal government to estimate loss from a variety of threats, …


Thinking Aloud In The Science Classroom: Can A Literacy Strategy Increase Student Learning In Science?, Lindsey Joan Mockel Aug 2013

Thinking Aloud In The Science Classroom: Can A Literacy Strategy Increase Student Learning In Science?, Lindsey Joan Mockel

Dissertations and Theses

This research study investigated the effect of using the think aloud protocol while reading informational text on students' ability to learn from text in a secondary science classroom. The participants in this study were high school students (n=47) in three classes of a mixed-grade Integrated Biology, Chemistry, and Physics course. The study tracked student achievement during a four-week curriculum unit on the theory of evolution and evidence for biological evolution. All students received instruction on using the think aloud protocol, and all students practiced the think aloud protocol when reading short articles related to scientific evidence for evolution. The researcher …


Incorporating Chemical Activity And Relative Humidity Effects In Regional Air Quality Modeling Of Organic Aerosol Formation, Marguerite Colasurdo Marks Aug 2013

Incorporating Chemical Activity And Relative Humidity Effects In Regional Air Quality Modeling Of Organic Aerosol Formation, Marguerite Colasurdo Marks

Dissertations and Theses

Atmospheric particulate matter is known to have significant effects on human health, visibility, and global climate. The magnitudes of these effects, however, depend in complex ways on chemical composition, relative humidity, temperature, phase state, and other parameters. Current regional air quality models such as CMAQ (Community Multiscale Air Quality model) ignore many of these considerations, and consider that the formation of secondary organic aerosol (SOA) can be calculated by assuming thermodynamic ideality in the organic particulate matter (OPM) phase as well as negligible uptake of water into the OPM phase. Theoretical predictions and model simulations considering non-ideality and water uptake …